The present invention relates to a bar connecting clamp.
The invention may preferably be used, though not exclusively, for connecting bars supporting tools on folding-gluing machines employed in the graphics industry (hereinafter referred to simply as “graphic machines”), to which the following description refers purely by way of example.
Graphic machines normally comprise a conveying surface on which blanks of sheet paper material are conveyed successively; and a number of tools suspended over the conveying surface, and which interact with the blanks for conveyance purposes (pressure rollers) or to perform various processing operations (folding, gluing, etc.). By varying the type, number and sequence of the tools, more or less complex paper articles can be obtained, such as folders with one or more pockets, CD holders, etc.
In one known solution, the tools are supported on vertical bars, in turn fixed to horizontal bars suspended over the conveying surface and fixed directly or indirectly to the machine structure. In one known solution, the horizontal and vertical bars are connected by clamps comprising a substantially parallelepiped-shaped body in which prismatic guides are machined with the same cross section as the bars for connection; and pressure screws are screwed into the body to lock the bars longitudinally inside the respective seats.
One problem of known clamps is high cost, on account of the machining involved and the large amount of waste material removed in the form of chips during machining. Another problem is the need for clamps with guides of different sections for different types of bars, which further increases overall tooling cost.